videos in AudioSet
A list of about a million ten-second YouTube clips, each labelled with the sounds in it, that Google published in 2017. Labs use it to train and test general audio and music models.
Including In the Gloaming - featuring James McCabe on Bb Cornet, Over the Rainbow by Alan Morrison. Tenor Horn and Piano., Rondo from Mozart's 3rd Horn Concerto (K447) (Tenor horn and piano)